recommendation for equipment on MPLS network

[smesiatowsky]

We current are a smaller company reaching the brink of the enterprise level. We currently have a data center at our head quarters, and 30 remote sites connecting with either a managed ADSL connection, or through an VPN tunnel through the Internet. We are currently going to move to an MPLS network. 5 remote sites have 10 users and are going to be connected to the MPLS network via an ADSL or T1

15 remote sites only have 10 ? 20 users and will have a 10 MB fiber connection to the MPLS

8 remote sites have 30 users and will have a 10 MB fiber connection to the MPLS

2 remote sites have 50 and 70 users and will have a 10 MB fiber connection to the MPLS

1 site has 250 users and will have a 100 MB fiber connection to the MPLS

And HQ will have 250 users and have a 100 MB fiber connection to the MPLS

We are also implementing VoIP in all the offices so we need some form of QOS

We were looking at three options for MPLS

Option 1: layer 3 MPLS and share our routing info with our carrier

Option 2: layer 3 MPLS, and using GRE routes so we do not need to share routing info

Option 3: layer 2 with QoS support

What size of routers do we need in our data center, and other main site?

Does GRE have much performance impact? And if so, do we need to go with a larger router if we use GRE?

We are going to use integrated services routers in the remote sites to support SRST, so we were thinking to go with 2801?s for smaller shops, to 2851?s for the larger sites.

For the main site and data center, we were thinking of either 3845 or 7204vxr.

Would the 3845 do the trick? Or would we need to move up to the 7204vxr?

How exactly can we size our routers correctly? Do most people just usually go with experience? Or use some form of specs? And what specs should I be looking for?

Any suggestions or comments?

Thanks for your help

[mahesh-gohil]

Dear sir,

I request u to post this query at MPLS section under service provider Menu

I am sure u will get answered

regards

mahesh

[bond12345]

Hi,

As you are going for Hub & Spoke Locations it is better to go for Option 3: layer 2 with QoS support.At spoke location it is fine with 2821series router and at Hub location you can go with 3845 which supports voip.If the cost is not a constraint the 7204vxr is best one.Only from spoke location you need to propagate the routes into service provider network and 2821 is fine.Also you run EBGP with service provider with private AS.

[mark.edwards]

Hi, personally I would not consider using option 2 (GRE tunnels). You say the reason for this is so you don't share routes with the provider but your routes will be in a seperate routing instance (VRF) on the providers network. It sort of defeats the point of a L3 VPN if you use GRE over the top.